Theme hints:
This is one where there’s a “key clue.” There isn’t one in every themed xword, but it’s a good idea to scan all the clues quickly to see if there’s one that ties the rest together. Understand also that you may not “get” that special clue until you’ve put in most or all of the other long answers. That’s especially true here, since the clue itself doesn’t tell you much of anything immediately.
The “key clue” is especially important here because it tells you that only the across clues are involved in the theme, not the long down clues.
By the way, once I’d solved it, I still had some doubts about the “and figuratively” part of the clue. It seemed partially true, not entirely. The answers to 17-, 30- and 45-Across are definitely literally what the answer to 60-Across says they are.
Specific hints:
Barbershop floor sweepings: Remember that not all plurals in S.
Letter before omega: Omega is actually the last letter of the Greek alphabet. ‘course that doesn’t tell you what comes before it. It isn’t what you’d expect if you’re thinking of the English alphabet.
Genre for Andy Warhol: Sounds like something that your kids toast for breakfast.
I can’t take any more: 3 words, but don’t get ripped up about it!
Carved Idol: 2 words, but don’t go worshipping it!